1. Field of the Invention
The present invention relates generally to a method and apparatus for playing back a video. More particularly, the present invention relates to a video playback method and apparatus capable of providing additional information included in a video to a plurality of users individually.
2. Description of the Related Art
Digital Multimedia Broadcasting (DMB) is one of the services that provide video data over portable terminals. DMB, which may provide stream-type broadcast signals, can also broadcast DMB signals, to which MPEG-4 Binary Format for Scenes (BIFS) is applied, at the DMB broadcasting station. The term ‘MPEG-4 BIFS’, as used herein, refers to an MPEG-4 scene description. DMB provides MPEG-4 BIFS as auxiliary data (or additional information) in addition to an audio/video stream, and BIFS composes a scene in units of objects and supports a particular one of BIFS nodes, which responds to a user's input so that the user can click menus and buttons while viewing contents, thereby enabling interactive communication.
Generally, MPEG-4 refers to a digital bit stream protocol for encoding audio data, video data and objects, and means a standard capable of digitally describing and delivering various multimedia contents. Since MPEG-4 is an object-based description system, there is a need for scene description information for making or composing each scene.
Such scene description information is referred to as Binary Format for Scenes (BIFS). Herein, BIFS refers to an MPEG-4 scene description protocol, and it means information used for making MPEG-4 objects, describing an interface with the MPEG-4 objects, moving the MPEG-4 objects, and composing/mixing the MPEG-4 objects to allow them to interact with each other. Therefore, a DMB receiver, which receives the MPEG-4 BIFS-based DMB data, can receive objects constituting DMB contents, compose a scene using them according to BIFS, and provide the scene to the user.
Accordingly, MPEG-4 BIFS-based DMB service can be provided to a personal portable terminal so that the user can click menus and buttons while viewing the contents.
However, there is a problem in that when the MPEG-4 BIFS-based DMB service is provided to a large-sized display device such as a large-sized electric bulletin board aimed at providing information to a plurality of users, there is difficulty in realizing the environment where the plurality of users can select their own desired objects individually through the large-sized display device. Further, there also is difficulty in implementing the environment that individually provides particular data the plurality of users want.